FIFA announced on Friday it is extending its relaxation of rules forcing clubs to release players during international windows until the end of April.
Clubs can refuse to release their players if they would have to quarantine on their return to club duty due to coronavirus regulations.
"The Bureau of the FIFA Council has decided to provide additional flexibility regarding the release of players for national team duty and the registration of players with clubs in competitions that remain disrupted by the pandemic," FIFA said in a statement.
The measures could have a significant affect for English-based players with Portugal and South American countries among a number of nations where there is currently no elite sport exemption from a 10-day quarantine requirement.
Manchester City's Portugal trio of Bernardo Silva, Ruben Dias and Joao Cancelo are among those who could miss three World Cup qualifiers against Azerbaijan, Serbia and Luxembourg.
Liverpool's Brazil contingent of Alisson Becker, Fabinho and Roberto Firmino, Colombia duo James Rodriguez and Yerry Mina at Everton and Manchester United's Uruguay striker Edinson Cavani are among the South American stars at risk of missing two rounds of World Cup qualifiers.
Brazil are due to host Argentina on March 31.
FIFA also adopted other measures to cope with the disruption caused by Covid-19 to fixture schedules.
National football associations can ask to alter start and end dates to the season, following the precedent set last season when many major leagues finished late after a three-month pause due to the pandemic.
In June, the global footballers' union (FIFPro) said it was worried about the crowded schedule players face.
The current campaign began weeks after the last and will be followed by the postponed Euros and Olympics.
To help deal with the increased amount of games, UEFA has allowed up to five substitutions to be made in all European club and international matches this term.